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1.
Hum Gene Ther ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767504

RESUMO

Early diagnosis and intervention are pivotal in reducing colorectal cancer (CRC) incidence and enhancing patient outcomes. In this study, we focused on three genes, AQP8, GUCA2B, and SPIB, which exhibit high co-expression and play crucial roles in suppressing early-stage CRC. Our objective was to identify key miRNAs that can mitigate CRC tumorigenesis and modulate the co-expression network involving these genes. We conducted a comprehensive analysis using large-scale tissue mRNA data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus to validate the co-expression of AQP8, GUCA2B, and SPIB, and to assess their diagnostic and prognostic significance in CRC. mRNA-miRNA interactions were examined using MiRNet and the Encyclopedia of RNA Interactomes. Furthermore, using various molecular techniques, we conducted miRNA inhibitor transfection experiments in HCT116 cells to evaluate their effects on cell growth, migration, and gene/protein expression. Our findings revealed that, compared to normal tissues, AQP8, GUCA2B, and SPIB exhibited high co-expression and were downregulated in CRC, particularly during tumorigenesis. OncoMirs, hsa-miR-182-5p, and hsa-miR-27a-3p, were predicted to regulate these genes. MiRNA inhibition experiments in HCT116 cells demonstrated the inhibitory effects of miR-27a-3p and miR-182-5p on GUCA2B mRNA and protein expression. These miRNAs promoted the proliferation of CRC cells, possibly through their involvement in the GUCA2B-GUCY2C axis, which is known to promote tumor growth. While the expressions of AQP8 and SPIB were barely detectable, their regulatory relationship with hsa-miR-182-5p remained inconclusive. Our study confirms that hsa-miR-27a-3p and hsa-miR-182-5p are oncomiRs in CRC. These miRNAs may contribute to GUCY2C dysregulation by downregulating GUCA2B, which encodes uroguanylin. Consequently, hsa-miR-182-5p and hsa-miR-27a-3p show promise as potential targets for early intervention and treatment in the early stages of CRC.

2.
medRxiv ; 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37745479

RESUMO

Background: Anesthetic agents including ketamine and nitrous oxide have shown antidepressant properties when appropriately dosed. Our recent open-label trial of propofol, an intravenous anesthetic known to elicit transient positive mood effects, suggested that it may also produce robust and durable antidepressant effects when administered at a high dose that elicits an electroencephalographic (EEG) burst-suppression state. Here we report findings from a randomized controlled trial ( NCT03684447 ) that compared two doses of propofol. We hypothesized greater improvement with a high dose that evoked burst suppression versus a low dose that did not. Methods: Participants with moderate-to-severe, treatment-resistant depression were randomized to a series of 6 treatments at low versus high dose (n=12 per group). Propofol infusions were guided by real-time processed frontal EEG to achieve predetermined pharmacodynamic criteria. The primary and secondary depression outcome measures were the 24-item Hamilton Depression Rating Scale (HDRS-24) and the Patient Health Questionnaire (PHQ-9), respectively. Secondary scales measured suicidal ideation, anxiety, functional impairment, and quality of life. Results: Treatments were well tolerated and blinding procedures were effective. The mean [95%-CI] change in HDRS-24 score was -5.3 [-10.3, -0.2] for the low-dose group and -9.3 [-12.9, -5.6] for the high-dose group (17% versus 33% reduction). The between-group effect size (standardized mean difference) was -0.56 [-1.39, 0.28]. The group difference was not statistically significant (p=0.24, linear model). The mean change in PHQ-9 score was -2.0 [-3.9, -0.1] for the low dose and -4.8 [-7.7, -2.0] for the high dose. The between-group effect size was -0.73 [-1.59, 0.14] (p=0.09). Secondary outcomes favored the high dose (effect sizes magnitudes 0.1 - 0.9) but did not generally reach statistical significance (p>0.05). Conclusions: The medium-sized effects observed between doses in this small, controlled, clinical trial suggest that propofol may have dose-dependent antidepressant effects. The findings also provide guidance for subsequent trials. A larger sample size and additional treatments in series are likely to enhance the ability to detect dose-dependent effects. Future work is warranted to investigate potential antidepressant mechanisms and dose optimization.

3.
Viruses ; 15(7)2023 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-37515248

RESUMO

We developed a convenient method for amplifying the complete SARS-CoV-2 sequence using in-house RT-PCR without virus culture. Forty-one stored throat swabs and blood specimens were collected from eight SARS-CoV-2 infections at multiple time points. Total RNA was extracted using the QIAamp viral RNA mini kit and pooled for higher RNA levels. Only those positive specimens by commercial real-time RT-PCR (RT-qPCR) were selected and amplified by in-house RT-PCR for complete sequences, followed by sequencing. Phylogenetic trees and exploratory analyses were performed using MEGA 11 and Simplot 3.5.1 software. Swab samples had significantly higher total RNA concentrations than plasma (p < 0.01). Positive results were found mainly in swabs, but one was found in plasma. Successful gene amplification depended on Ct values (Ct < 38). A non-synonymous substitution was found in ORF1ab/Nsp3 (at NC045512.2 position 6312, C to A) and most spike protein mutations occurred in the S1 subunit (residues 14-685). The proposed method is time-saving and reliable for rapid genomic analysis. Increasing sample volume and pooling them for RNA extraction increases RNA concentration without culture. Combining nucleotide sequences from specific variable regions of the genome is more efficient than conventional methods.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnicas de Laboratório Clínico/métodos , Teste para COVID-19 , RNA Viral/genética , RNA Viral/análise , Sensibilidade e Especificidade
4.
J Microbiol Immunol Infect ; 56(3): 506-515, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36967265

RESUMO

BACKGROUND: Understanding the neutralizing antibody (NAb) titer against COVID-19 over time is important to provide information for vaccine implementation. The longitudinal NAb titer over one year after SARS-CoV-2 infection is still unclear. The purposes of this study are to evaluate the duration of the neutralizing NAb titers in COVID-19 convalescents and factors associated with the titer positive duration. METHODS: A cohort study followed COVID-19 individuals diagnosed between 2020 and 2021 May 15th from the COVID-19 database from the Taiwan Centers for Disease Control. We analyzed NAb titers from convalescent SARS-CoV-2 individuals. We used generalized estimating equations (GEE) and a Cox regression model to summarize the factors associated with NAb titers against COVID-19 decaying in the vaccine-free population. RESULTS: A total of 203 convalescent subjects with 297 analytic samples were followed for a period of up to 588 days. Our study suggests that convalescent COVID-19 in individuals after more than a year and four months pertains to only 25% of positive titers. The GEE model indicates that longer follow-up duration was associated with a significantly lower NAb titer. The Cox regression model indicated the disease severity with advanced condition was associated with maintaining NAb titers (adjusted hazard ratio: 2.01, 95% CI: 1.11-3.63) and that smoking was also associated with higher risk of negative NAb titers (adjusted hazard ratio: 0.55, 95% CI: 0.33-0.92). CONCLUSIONS: Neutralizing antibody titers diminished after more than a year. The antibody titer response against SARS-CoV-2 in naturally convalescent individuals provides a reference for vaccinations.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Estudos de Coortes , Taiwan/epidemiologia , Anticorpos Neutralizantes , Anticorpos Antivirais
5.
Viruses ; 14(10)2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36298695

RESUMO

Persons who inject drugs (PWID) and their risk-related behaviors (e.g., unprotected sex and sharing needles/syringes/other injection equipment) have caused severe public health problems, especially in the rapid spread of HIV-1 and HCV. Here, we reconstructed the epidemic history of HIV-1 circulating recombinant form (CRF) 01_AE, CRF07_BC, and HCV subtype-6w among Taiwanese PWID. The timescales were estimated using phylogenetic and Bayesian coalescent analyses. The results revealed that CRF01_AE started to circulate in the Taiwanese PWID population in central Taiwan at 1992.5 (95% credible region: 1988.8-1995.9) and spread to other regions of Taiwan, while CRF07_BC was first identified in southern Taiwan at 2000.0 (95% CR: 1997.8-2002.2) and then spread northward to central-northern Taiwan. All HCV-6 strains were from Asia (that is, China, Myanmar, Taiwan, and Vietnam) and originated in 1928.1 (95% CR: 1890.2-1966.0). Furthermore, subtype-6w isolates from different regions of Taiwan appeared to share a common source that existed in the mid-1990s (95% CR: 1985.0-2001.8) or thereabouts. The routes of drug trafficking and the resulting high prevalence of HIV-1/HCV co-infections among PWID might have contributed to the virus transmission and promoted its spread worldwide. Long-term monitoring and policy implementation in at-risk populations would be useful for disease control.


Assuntos
Usuários de Drogas , Infecções por HIV , Soropositividade para HIV , HIV-1 , Hepatite C , Abuso de Substâncias por Via Intravenosa , Humanos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Filogenia , Teorema de Bayes , Hepatite C/epidemiologia , China/epidemiologia , Genótipo
6.
Pharmaceuticals (Basel) ; 14(5)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065500

RESUMO

Animal lectins are proteins with carbohydrate recognition activity. Galectins, the ß-galactoside binding lectins, are expressed in various cells and have been reported to regulate several immunological and physiological responses. Recently, some galectins have been reported to regulate some viral infections, including influenza A virus (IAV); however, the mechanism is still not fully understood. Thus, we aim to review systemically the roles of galectins in their antiviral functions against IAVs. The PRISMA guidelines were used to select the eligible articles. Results indicated that only Galectin-1, Galectin-3, and Galectin-9 were reported to play a regulatory role in IAV infection. These regulatory effects occur extracellularly, through their carbohydrate recognition domain (CRD) interacting with glycans expressed on the virus surface, as well as endogenously, in a cell-cell interaction manner. The inhibition effects induced by galectins on IAV infection were through blocking virus-host receptors interaction, activation of NLRP-3 inflammasome, augment expression of antiviral genes and related cytokines, as well as stimulation of Tim-3 related signaling to enhance virus-specific T cells and humoral immune response. Combined, this study concludes that currently, only three galectins have reported antiviral capabilities against IAV infection, thereby having the potential to be applied as an alternative anti-influenza therapeutic strategy.

7.
Int J Oncol ; 51(5): 1415-1426, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29048611

RESUMO

Increasing evidence suggests a link between persistent human cytomegalovirus (HCMV) infection and cancer. Although the role of HCMV in cancer is still elusive, recent studies revealed the presence of HCMV nucleic acids and proteins in different cancer types such as glioblastoma, colorectal, breast, and prostate cancers, and neuroblastoma. Although HCMV may not be directly associated with the neoplastic transformation, the presence of HCMV DNA in the tumorous tissue has been associated with altered clinical outcomes in cancer patients. However, the mechanisms involved in the association between colorectal cancer (CRC) and HCMV are unclear. In this study, we investigated the influence of HCMV infection on CRC or their derived cells. Proliferation and migration assays revealed a high infection efficiency in CRC-derived HT29 and SW480 'stem­like' cells. After 24, 48 and 72 h of HCMV infection, both HT29 and SW480 parental and stem­like cells showed a significant increase in cell proliferation and viability (p<0.0001). Moreover, HCMV infection promoted cell migration. These results demonstrate a significant phenotypic alteration in the CRC cell line upon HCMV infection. Using epithelial to mesenchymal transition (EMT) assays, we demonstrated that the EMT markers and driver genes were upregulated during the virus infection. The WNT signaling pathway, which is associated with the proliferation and migration of CRC cells, was upregulated (6-fold) in HCMV-infected cells as compared to the non­infected cells at day 7 from infection.


Assuntos
Neoplasias Colorretais/genética , Infecções por Citomegalovirus/genética , Citomegalovirus/patogenicidade , Células-Tronco Neoplásicas/virologia , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/complicações , Neoplasias Colorretais/patologia , Neoplasias Colorretais/virologia , Citomegalovirus/genética , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/virologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HT29 , Humanos , Células-Tronco Neoplásicas/patologia , Ativação Transcricional/genética , Via de Sinalização Wnt/genética
8.
Oncotarget ; 8(13): 21266-21280, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28177885

RESUMO

Metastasis accounts for the high mortality rate associated with colorectal cancer (CRC), but metastasis regulators are not fully understood. To identify a novel gene involved in tumor metastasis, we used oligonucleotide microarrays, transcriptome distance analyses, and machine learning algorithms to determine links between primary and metastatic colorectal cancers. Aminopeptidase A (APA; also known as ENPEP) was selected as our focus because its relationship with colorectal cancer requires clarification. Higher APA mRNA levels were observed in patients in advanced stages of cancer, suggesting a correlation between ENPEP and degree of malignancy. Our data also indicate that APA overexpression in CRC cells induced cell migration, invasion, anchorage-independent capability, and mesenchyme-like characteristics (e.g., EMT markers). We also observed TWIST induction in APA-overexpressing SW480 cells and TWIST down-regulation in HT29 cells knocked down with APA. Both APA silencing and impaired APA activity were found to reduce migratory capacity, cancer anchorage, stemness properties, and drug resistance in vitro and in vivo. We therefore suggest that APA enzymatic activity affects tumor initiation and cancer malignancy in a TWIST-dependent manner. Results from RT-qPCR and the immunohistochemical staining of specimens taken from CRC patients indicate a significant correlation between APA and TWIST. According to data from SurvExpress analyses of TWIST1 and APA mRNA expression profiles, high APA and TWIST expression are positively correlated with poor CRC prognosis. APA may act as a prognostic factor and/or therapeutic target for CRC metastasis and recurrence.


Assuntos
Transformação Celular Neoplásica/metabolismo , Neoplasias Colorretais/metabolismo , Glutamil Aminopeptidase/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas Nucleares/biossíntese , Proteína 1 Relacionada a Twist/biossíntese , Animais , Transformação Celular Neoplásica/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/fisiologia , Xenoenxertos , Humanos , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese Sítio-Dirigida , Células-Tronco Neoplásicas/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase em Tempo Real , Análise Serial de Tecidos , Regulação para Cima
9.
Dev Comp Immunol ; 67: 8-17, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27984103

RESUMO

In 2009, a swine-origin influenza A virus - A(H1N1)pdm09 - emerged and has became a pandemic strain circulating worldwide. The hemagglutinin (HA) of influenza virus is a potential target for the development of anti-viral therapeutic agents. Here, we generated mAbs by immunization of baculovirus-insect expressing trimeric recombinant HA of the A(H1N1)pdm09 strain. Results indicated that the mAbs recognized two novel neutralizing and protective epitopes-"STAS" and "FRSK" which located near Cb and Ca1 antigenic regions respectively and were conserved in almost 2009-2016 influenza H1N1 stains. The mAb 12E11 demonstrated higher protective efficacy than mAb 8B10 in mice challenge assay. Both mAb pretreatments significantly reduced virus titers and pro-inflammatory cytokines in mice lung postinfection (p < 0.01), and showed prophylactic and therapeutic efficacies even 48 h postinfection (p < 0.05). Combination therapy using the mAbs with oseltamivir pre- and post-treatment showed synergistic therapeutic effect in mice model (p < 0.01). Further investigation for clinical application in humans is warranted.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Imunoterapia/métodos , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Infecções por Orthomyxoviridae/terapia , Vacinas Virais/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antivirais/isolamento & purificação , Terapia Combinada , Cães , Sinergismo Farmacológico , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Epitopos Imunodominantes/imunologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Oseltamivir/uso terapêutico , Multimerização Proteica , Suínos
10.
Emerg Infect Dis ; 22(11): 1981-1984, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27767908

RESUMO

We identified 78 imported chikungunya cases in Taiwan during 2006-2014. Sixty-six (84.6%) cases were initially suspected to be dengue, which indicates the necessity for laboratory diagnostics in differentiation between dengue and chikungunya. Results also emphasize the need for active surveillance of febrile illness at points of entry.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/virologia , Febre de Chikungunya/história , Vírus Chikungunya/genética , Doenças Transmissíveis Importadas/história , Genótipo , História do Século XXI , Humanos , Filogenia , Prevalência , Taiwan/epidemiologia , Viagem
11.
J Microbiol Immunol Infect ; 49(4): 477-86, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25442859

RESUMO

BACKGROUND: The swine-origin influenza A (H1N1) virus (S-OIV) has come to the forefront since 2009 and was identified as a new reassortant strain. The hemagglutinin (HA) glycoprotein mediates virus binding, contains antigenic regions recognized by neutralizing antibodies, and is associated with viral cross-species infection and adaption. The comparison study of codon usage preferences in influenza viral genomes was less extensive. In this study, we used codon usage pattern analyses to validate the adaption and origins of S-OIV. METHODS: Codon usage pattern was used to estimate the host adaption of S-OIVs. Phylogenetic analysis of the HA gene was conducted to understand the phylogeny of H1N1 viruses isolated from different hosts. Amino acid signature pattern on antigenic sites of HA was analyzed to understand the antigenic characteristics. RESULTS: Results of phylogenetic analyses of HA gene indicate that S-OIVs group in identical clusters. The synonymous codon usage pattern analyses indicate that the effective number of codons versus GC content at the third codon position in the HA1 gene slightly differ from those in swine H1N1 and gradually adapted to human. Our data indicate that S-OIV evolution occurred according to positive selection within these antigenic regions. A comparison of antigenic site amino acids reveals similar signature patterns between S-OIV and 1918 human influenza strains. CONCLUSION: This study proposes a new and effective way to gain a better understanding of the features of the S-OIV genome and evolutionary processes based on the codon usage pattern. It is useful to trace influenza viral origins and cross-species virus transmission.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Especificidade de Hospedeiro/genética , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/virologia , Ligação Viral , Substituição de Aminoácidos/genética , Animais , Composição de Bases/genética , Códon/genética , Genoma Viral/genética , Humanos , Filogenia , Suínos , Doenças dos Suínos/virologia
12.
Protein Sci ; 24(12): 1934-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26362012

RESUMO

RNase T is a classical member of the DEDDh family of exonucleases with a unique sequence preference in that its 3'-to-5' exonuclease activity is blocked by a 3'-terminal dinucleotide CC in digesting both single-stranded RNA and DNA. Our previous crystal structure analysis of RNase T-DNA complexes show that four phenylalanine residues, F29, F77, F124, and F146, stack with the two 3'-terminal nucleobases. To elucidate if the π-π stacking interactions between aromatic residues and nucleobases play a critical role in sequence-specific protein-nucleic acid recognition, here we mutated two to four of the phenylalanine residues in RNase T to tryptophan (W mutants) and tyrosine (Y mutants). The Escherichia coli strains expressing either the W mutants or the Y mutants had slow growth phenotypes, suggesting that all of these mutants could not fully substitute the function of the wild-type RNase T in vivo. DNA digestion assays revealed W mutants shared similar sequence specificity with wild-type RNase T. However, the Y mutants exhibited altered sequence-dependent activity, digesting ssDNA with both 3'-end CC and GG sequences. Moreover, the W and Y mutants had reduced DNA-binding activity and lower thermal stability as compared to wild-type RNase T. Taken together, our results suggest that the four phenylalanine residues in RNase T not only play critical roles in sequence-specific recognition, but also in overall protein stability. Our results provide the first evidence showing that the π-π stacking interactions between nucleobases and protein aromatic residues may guide the sequence-specific activity for DNA and RNA enzymes.


Assuntos
DNA de Cadeia Simples/metabolismo , Proteínas de Escherichia coli/química , Escherichia coli/crescimento & desenvolvimento , Exorribonucleases/química , Sequência de Aminoácidos , Domínio Catalítico , Dicroísmo Circular , Estabilidade Enzimática , Escherichia coli/enzimologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Exorribonucleases/genética , Exorribonucleases/metabolismo , Modelos Moleculares , Ligação Proteica , Estrutura Secundária de Proteína , Temperatura
13.
J Med Virol ; 87(9): 1462-70, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25946552

RESUMO

In 2012, a new norovirus GII.4 variant (GII.4 Sydney) emerged and caused the majority of the acute gastroenteritis outbreaks in Australia, Asia, Europe, and North America. We examined the epidemiologic and molecular virologic characteristics of reported acute gastroenteritis outbreaks determined to be caused by norovirus in Taiwan from January 2012 to December 2013. A total of 253 (45.7%) of 552 reported acute gastroenteritis outbreaks tested positive for norovirus, of which 165 (65.5%) were typed as GII.4 Sydney. GII.4 Sydney outbreaks were reported from all geographic areas of Taiwan and occurred most frequently in schools (35.8%) and long-term care facilities (24.2%). Person-to-person transmission was identified in 116 (70.3%) of the outbreaks. Phylogenetic analyses of full-length ORF2 of eight specimens indicated that GII.4 Sydney strains detected in Taiwan were closely related to strains detected globally. Continued outbreak surveillance and strain typing are needed to provide information on epidemiologic and virologic trends of novel norovirus strains.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Surtos de Doenças , Norovirus/classificação , Norovirus/genética , Infecções por Caliciviridae/transmissão , Fezes/virologia , Gastroenterite/virologia , Genótipo , Humanos , Norovirus/isolamento & purificação , Norovirus/patogenicidade , Filogenia , Análise de Sequência de DNA , Taiwan/epidemiologia , Fatores de Tempo
14.
Mol Med ; 20: 684-96, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25535034

RESUMO

Glycine N-methyltransferase (GNMT) is known for its function as a tumor suppressor gene. Since 100% of female Gnmt(-/-) mice developed hepatocellular carcinoma, we hypothesized that Gnmt(-/-) mice may have defective immune surveillance. In this study, we examined the immune modulation of GNMT in T-cell responses using experimental autoimmune encephalomyelitis (EAE). The results showed that EAE severity was reduced significantly in Gnmt(-/-) mice. Pathological examination of the spinal cords revealed that Gnmt(-/-) mice had significantly lower levels of mononuclear cell infiltration and demyelination than the wild-type mice. In addition, quantitative real-time PCR showed that expression levels of proinflammatory cytokines, including interferon (IFN)-γ and interleukin (IL)-17A, were much lower in the spinal cord of Gnmt(-/-) than in that of wild-type mice. Accordingly, myelin oligodendrocyte glycoprotein (MOG)-specific T-cell proliferation and induction of T-helper (Th)1 and Th17 cells were markedly suppressed in MOG(35-55)-induced Gnmt(-/-) mice. Moreover, the number of regulatory T (Treg) cells was increased significantly in these mice. When the T-cell receptor was stimulated, the proliferative capacity and the activation status of mTOR-associated downstream signaling were decreased significantly in Gnmt(-/-) CD4(+) T cells via an IL-2- and CD25-independent manner. Moreover, GNMT deficiency enhanced the differentiation of Treg cells without affecting the differentiation of Th1 and Th17 cells. Furthermore, the severity of EAE in mice adoptive transferred with GNMT-deficient CD4(+) T cells was much milder than in those with wild-type CD4(+) T cells. In summary, our findings suggest that GNMT is involved in the pathogenesis of EAE and plays a crucial role in the regulation of CD4(+) T-cell functions.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Glicina N-Metiltransferase/imunologia , Linfócitos T/imunologia , Animais , Citocinas/imunologia , Feminino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Serina-Treonina Quinases TOR/imunologia
15.
Infect Genet Evol ; 28: 530-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25281207

RESUMO

In 2006, two rotavirus vaccines (Rotarix and RotaTeq) became available on the private market in Taiwan. Although vaccine coverage is currently low, molecular surveillance of rotavirus strains can provide pertinent information for evaluation of the potential impact of vaccine introduction and infection control. During January 2008-December 2011, children aged <5 years hospitalized with acute gastroenteritis were enrolled from sentinel surveillance hospitals in three geographic areas of Taiwan. Fecal specimens collected from enrolled patients were tested for rotavirus by enzyme immunoassay and reverse transcriptase-polymerase chain reaction. For genotyping, gene specific primer sets were used to amplify and sequence the genes encoding the neutralization antigens, VP7 and VP4. The resulting sequences were then subjected to phylogenetic analysis. In brief, a total of 4,052 fecal specimens were tested and 742 (18%) samples were positive for rotavirus. The annual range of rotavirus positive specimens varied between 16% and 20.7%. Of all specimens, genotype G1P[8] (63.3%) was the predominant strain, followed by G2P[4] (12.5%), G3P[8] (11.7%), and G9P[8] (5.1%). Uncommon strains were also detected in low percentages. We observed that the rotavirus positivity rate steadily decreased from 21% to 16% during 2008-2010, then slightly increased to 20% in 2011, when an increase in the number of G2P[4] cases was observed. Sequence and phylogenetic analysis was carried out to help understand any potential changes of G2P[4] rotaviruses over time. A number of G2P[4] strains collected between 2004 and 2011 were analyzed in detail and our analyses showed marked genetic and antigenic variability in the VP7 and VP4 genes. The Taiwanese strains could be classified into two major G2 VP7 lineages (IV and V) and two major P[4] VP4 lineages (IV and V) and several minor sublineages within lineage IV. Lineage V within both G2 and P[4] represented newly recognized genetic variants of the respective genotypes. The distribution of individual combinations of the G2 and P[4] (sub)lineages showed some temporal variations. This study provides further evidence for the great genetic diversity among G2P[4] strains and helps understand the epidemiological trends of these strains among children in Taiwan.


Assuntos
Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Sequência de Aminoácidos , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral , Alinhamento de Sequência , Análise de Sequência de DNA , Taiwan/epidemiologia , Proteínas Virais/química , Proteínas Virais/genética
16.
Biochem Biophys Res Commun ; 451(2): 208-14, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25073113

RESUMO

The severe acute respiratory syndrome coronavirus (SARS-CoV) still carries the potential for reemergence, therefore efforts are being made to create a vaccine as a prophylactic strategy for control and prevention. Antibody-dependent enhancement (ADE) is a mechanism through which dengue viruses, feline coronaviruses, and HIV viruses take advantage of anti-viral humoral immune responses to infect host target cells. Here we describe our observations of SARS-CoV using ADE to enhance the infectivity of a HL-CZ human promonocyte cell line. Quantitative-PCR and immunofluorescence staining results indicate that SARS-CoV is capable of replication in HL-CZ cells, and of displaying virus-induced cytopathic effects and increased levels of TNF-α, IL-4 and IL-6 two days post-infection. According to flow cytometry data, the HL-CZ cells also expressed angiotensin converting enzyme 2 (ACE2, a SARS-CoV receptor) and higher levels of the FcγRII receptor. We found that higher concentrations of anti-sera against SARS-CoV neutralized SARS-CoV infection, while highly diluted anti-sera significantly increased SARS-CoV infection and induced higher levels of apoptosis. Results from infectivity assays indicate that SARS-CoV ADE is primarily mediated by diluted antibodies against envelope spike proteins rather than nucleocapsid proteins. We also generated monoclonal antibodies against SARS-CoV spike proteins and observed that most of them promoted SARS-CoV infection. Combined, our results suggest that antibodies against SARS-CoV spike proteins may trigger ADE effects. The data raise new questions regarding a potential SARS-CoV vaccine, while shedding light on mechanisms involved in SARS pathogenesis.


Assuntos
Anticorpos Antivirais/metabolismo , Síndrome Respiratória Aguda Grave/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2 , Animais , Linhagem Celular , Chlorocebus aethiops , Proteínas do Nucleocapsídeo de Coronavírus , Efeito Citopatogênico Viral , Humanos , Proteínas do Nucleocapsídeo/imunologia , Peptidil Dipeptidase A/metabolismo , Receptores de IgG/metabolismo , Receptores Virais/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Síndrome Respiratória Aguda Grave/etiologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Células Vero , Vacinas Virais/imunologia , Replicação Viral
17.
Exp Biol Med (Maywood) ; 239(6): 715-23, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24719374

RESUMO

The hallmark of systemic lupus erythematosus (SLE) is the presence of high levels of anti-double-stranded DNA autoantibody (anti-dsDNA) in sera. In addition, pathogen infections coincide frequently with the occurrence of lupus. Our study was designed to investigate the contribution of anti-dsDNA, extracellular and intracellular Toll-like receptors (TLRs), a family of pattern-recognition receptors for sensing invading pathogens, in the pathogenesis of lupus. Although cell surface-expressed TLR4 may promote lupus progression, intracellular nucleic acid-sensing TLR9 plays either stimulatory or protective roles in different murine lupus models. To examine the role of TLR4, TLR9, and anti-dsDNA in SLE, we generated transgenic mice carrying anti-dsDNA antibody transgene and challenged the mice with TLR4- and TLR9-agonists, lipopolysaccharides (LPS), and CpG oligodeoxynucleotide (CpG ODN1826 and 2216), respectively. Splenocytes from these mice were found to secrete higher levels of interleukin-10 (IL-10) and anti-dsDNA when treated with a combination of TLR4 and TLR9 agonists (LPS + CpG). In addition, the transgenic mice were intraperitoneally administered with CpG or combined CpG and LPS to determine whether extracellular TLR4 and intracellular TLR9 activations could affect lupus progression in vivo. It was found that serum levels of anti-dsDNA antibodies and interferon-alpha were higher in CpG + LPS-treated transgenic mice than those in non-transgenic mice. Besides, elevated levels of proteinuria, blood urine nitrogen, and immune complex depositions in kidney were found in treated transgenic mice. Anti-dsDNA and simultaneous activation of surface-expressed TLR4 and endosomal TLR9 are crucial to promote the lupus progression.


Assuntos
Anticorpos Antinucleares/metabolismo , Endossomos/metabolismo , Regulação da Expressão Gênica , Lúpus Eritematoso Sistêmico/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Animais , Anticorpos Antinucleares/genética , Endossomos/genética , Lipopolissacarídeos/farmacologia , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/patologia , Camundongos , Camundongos Transgênicos , Oligodesoxirribonucleotídeos/farmacologia , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/genética , Receptor Toll-Like 9/genética
18.
J Med Microbiol ; 61(Pt 7): 990-997, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22466032

RESUMO

The molecular characterization of genotype P[6] rotavirus strains collected from children admitted to hospital with acute dehydrating diarrhoea during a 6-year surveillance period in Taiwan is described in this study. In total, three G4P[6] strains, one G5P[6] and one G12P[6] were characterized by sequencing and phylogenetic analysis of the VP4, VP7, VP6 and NSP4 genes. Whilst all four genes of the single Taiwanese G12P[6] strain clustered with the respective genes of globally common human rotavirus strains, the G4 and G5 strains showed remarkable similarities to porcine rotavirus strains and putative porcine-origin human P[19] strains reported previously from Taiwan. The overall proportion of porcine rotavirus-like strains in Taiwan remains around 1 % among hospitalized children; however, the circulation and sporadic transmission of these heterotypic strains from pigs to humans could pose a public-health concern. Therefore, continuation of strain monitoring is needed in the vaccine era to detect any possible vaccine breakthrough events associated with the introduction of such heterologous rotavirus strains.


Assuntos
Diarreia/virologia , Gastroenterite/virologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/isolamento & purificação , Animais , Pré-Escolar , Análise por Conglomerados , Genótipo , Hospitais , Humanos , RNA Viral/genética , Rotavirus/genética , Análise de Sequência de DNA , Homologia de Sequência , Suínos , Doenças dos Suínos/virologia , Taiwan , Proteínas Virais/genética , Zoonoses/virologia
19.
Viral Immunol ; 24(5): 421-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21958371

RESUMO

One-hundred and thirty confirmed cases of severe acute respiratory syndrome (SARS) were recruited to evaluate their anti-SARS-coronavirus (CoV) antibody status and human leukocyte antigen (HLA) types in September 2006, 3 y after the SARS outbreaks in Taiwan. Western blot assay showed that 6.9% of participants still had anti-spike and anti-nucleocapside antibodies. A case-control study of the association of HLA with SARS revealed that the HLA-Cw1502 and DR0301 alleles conferred resistance against SARS infection (p<0.05).


Assuntos
Anticorpos Antivirais/sangue , Povo Asiático/genética , Resistência à Doença/genética , Antígenos HLA-C/genética , Antígeno HLA-DR3/genética , Síndrome Respiratória Aguda Grave/genética , Adulto , Anticorpos Neutralizantes/sangue , Estudos de Casos e Controles , Resistência à Doença/imunologia , Feminino , Genótipo , Teste de Histocompatibilidade , Humanos , Masculino , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/imunologia , Taiwan/epidemiologia
20.
J Med Virol ; 83(7): 1279-87, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21567431

RESUMO

We previously reported the detection of genotype P[19] rotavirus strains from children hospitalized with acute dehydrating diarrhea during a 5-year surveillance period in Taiwan. The characterization of five P[19] strains (0.4% of all typed), including three G3P[19], a novel G5P[19], and a unique G9P[19] genotype is described in this study. Phylogenetic analysis of the VP4, VP7, VP6, and NSP4 genes was performed, which demonstrated novel lineages for respective genotypes of the VP4 and the VP7 genes. The sequence similarities of the P[19] VP4 gene among Taiwanese human strains was higher (nt, 91.5-96.2%; aa, 93.7-97.6%) than to other P[19] strains (nt, 83.5-86.6%; aa, 89.4-94.1%) from different regions of the world. The VP7 gene of the three G3P[19] Taiwanese strains shared up to 93.4% nt and 97.5% aa identity to each other but had lower similarity to reference strain sequences available in GenBank (nt, <90.1%; aa, <95.6%). Similarly, the VP7 gene of the novel G5P[19] strain was only moderately related to the VP7 gene of reference G5 strains (nt, 82.2-87.3%; aa, 87.0-93.1%), while the VP7 gene of the single G9P[19] strain was genetically distinct from other known human and animal G9 rotavirus strains (nt, ≤ 92.0%; aa, ≤ 95.7%). Together, these findings suggest that the Taiwanese P[19] strains originated by independent interspecies transmission events. Synchronized surveillance of human and animal rotaviruses in Taiwan should identify possible hosts of these uncommon human rotavirus strains.


Assuntos
Proteínas do Capsídeo/genética , Diarreia/genética , Genes Virais , Infecções por Rotavirus/genética , Rotavirus , Proteínas não Estruturais Virais/genética , Doença Aguda , Antígenos Virais/genética , Sequência de Bases , Proteínas do Capsídeo/classificação , Criança , Diarreia/epidemiologia , Diarreia/virologia , Fezes/virologia , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , Polimorfismo Genético , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/classificação , Rotavirus/genética , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Análise de Sequência de DNA , Taiwan , Proteínas não Estruturais Virais/classificação
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